1. Field of the Invention
The present invention generally relates to wireless communication systems and, more particularly, to a method and apparatus for handover in a wireless communication device between wireless domains.
2. Description of the Related Art
The field of wireless communications has become increasingly important in today's society. One area associated with wireless communications relates to a handover process in a wireless communication device (also referred to as a handoff process). In general, a handover process refers to a scenario in which wireless communication is passed from one wireless base station to another base station, including those within one wireless domain or across multiple wireless domains. A handover is generally a response to geographic movement by a mobile station between wireless base stations as driven by movement across base stations within or across domains. For example, a handover may occur between base stations of a cellular network or between different cellular networks. In another example, a handover may occur between an outdoor wireless domain (e.g., a macro-cellular network) and an indoor wireless domain (e.g., a micro-cellular network or an indoor wireless local area network).
One technique for triggering handovers employs signal level comparisons between wireless domains at the wireless communication device and/or the base stations in communication with the wireless communication device. Signal level based handovers, however, are not reliable, especially when the base stations are deployed close to each other. For example, signal levels can fluctuate significantly due to multipath propagation, as well as system loading. Another technique for triggering handovers involves manual network selection. That is, the user must select the particular wireless domain with which to communicate. Manual network selection, however, is cumbersome, as the user needs to consciously perform network selection using the wireless communication device. Accordingly, there exists a need in the art for an improved method and apparatus for handover in a wireless communication device between wireless domains.